Index: core/kernel/db/db_tag_processor.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- core/kernel/db/db_tag_processor.php	(revision 15958)
+++ core/kernel/db/db_tag_processor.php	(revision )
@@ -1188,14 +1188,16 @@
 			$block_params['field_name'] = '';
 		}
 		else {
-			$block_params['field_name'] = $this->InputName($params); // depricated (produces warning when used as grid filter), but used in Front-End (submission create), admin (submission view)
+			// deprecated (produces warning when used as grid filter), but used in Front-End (submission create), admin (submission view)
+			$block_params['field_name'] = $this->InputName($params);
 		}
 
+		$selected_html = isset($params['selected']) ? $params['selected'] : 'selected';
 		$selected_param_name = array_key_exists('selected_param', $params) ? $params['selected_param'] : false;
+
 		if (!$selected_param_name) {
-			$selected_param_name = $params['selected'];
+			$selected_param_name = $selected_html;
 		}
-		$selected = $params['selected'];
 
 		$o = '';
 		if (array_key_exists('no_empty', $params) && $params['no_empty'] && !getArrayValue($options, '')) {
@@ -1203,35 +1205,93 @@
 			array_shift($options);
 		}
 
-		$index = 0;
+		$selected_option_keys = $this->getSelectedOptionKeys($value);
+
+		if ( isset($params['selected_only']) && $params['selected_only'] ) {
+			$options = $this->getSelectedOptions($options, $selected_option_keys);
+		}
+
+		$column_changed = false;
+		$option_number = $column_number = 1;
 		$option_count = count($options);
+		$column_count = isset($params['columns']) ? $params['columns'] : 1;
+		$options_per_column = ceil($option_count / $column_count);
 
-		if (strpos($value, '|') !== false) {
-			// multiple checkboxes OR multiselect
-			$value = explode('|', substr($value, 1, -1) );
-			foreach ($options as $key => $val) {
-				$block_params['key'] = $key;
-				$block_params['option'] = $val;
-				$block_params[$selected_param_name] = ( in_array($key, $value) ? ' '.$selected : '');
-				$block_params['is_last'] = $index == $option_count - 1;
+		$block_params['option_count'] = $option_count;
+
+		foreach ( $options as $option_key => $option_title ) {
+			$block_params['key'] = $option_key;
+			$block_params['option'] = $option_title;
+			$block_params[$selected_param_name] = $this->isOptionSelected($option_key, $selected_option_keys) ? ' ' . $selected_html : '';
+
+			$block_params['column_number'] = $column_number;
+			$block_params['column_changed'] = $column_changed;
+			$block_params['option_number'] = $option_number;
+			$block_params['is_last'] = $option_number == $option_count;
+
-				$o .= $this->Application->ParseBlock($block_params);
+			$o .= $this->Application->ParseBlock($block_params);
+			$column_changed = false;
+			$option_number++;
 
-				$index++;
+			if ( $option_number > $column_number * $options_per_column ) {
+				$column_number++;
+				$column_changed = true;
 			}
 		}
-		else {
+
+		return $o;
+	}
+
+	/**
+	 * Returns unified representation of selected options based on field value.
+	 *
+	 * @param mixed $field_value Field value.
+	 *
+	 * @return array
+	 */
+	protected function getSelectedOptionKeys($field_value)
+	{
+		if ( strpos($field_value, '|') !== false ) {
+			// multiple checkboxes OR multiselect
+			return explode('|', trim($field_value, '|'));
+		}
+
-			// single selection radio OR checkboxes OR dropdown
+		// single selection radio OR checkboxes OR dropdown
-			foreach ($options as $key => $val) {
-				$block_params['key'] = $key;
-				$block_params['option'] = $val;
-				$block_params[$selected_param_name] = (strlen($key) == strlen($value) && ($key == $value) ? ' '.$selected : '');
-				$block_params['is_last'] = $index == $option_count - 1;
-				$o .= $this->Application->ParseBlock($block_params);
+		return array("$field_value");
+	}
 
-				$index++;
+	/**
+	 * Returns only options, that have been selected.
+	 *
+	 * @param array $options              All options.
+	 * @param array $selected_option_keys Selected options.
+	 *
+	 * @return array
+	 */
+	protected function getSelectedOptions(array $options, array $selected_option_keys)
+	{
+		$ret = array();
+
+		foreach ( $options as $option_key => $option_title ) {
+			if ( $this->isOptionSelected($option_key, $selected_option_keys) ) {
+				$ret[$option_key] = $option_title;
 			}
 		}
-		return $o;
+
+		return $ret;
+	}
+
+	/**
+	 * Determines if given option is among selected ones.
+	 *
+	 * @param mixed $option_key           Option key.
+	 * @param array $selected_option_keys Selected options.
+	 *
+	 * @return boolean
+	 */
+	protected function isOptionSelected($option_key, array $selected_option_keys)
+	{
+		return in_array("$option_key", $selected_option_keys, true);
 	}
 
 	function PredefinedSearchOptions($params)
@@ -3156,4 +3216,4 @@
 
 		return '';
 	}
-}
\ No newline at end of file
+}